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arXiv · 0705.1295

Violation of the `Zero-Force Theorem' in the time-dependent Krieger-Li-Iafrate approximation

Michael Mundt·Stephan Kümmel·Robert van Leeuwen·Paul-Gerhard Reinhard
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Abstract

We demonstrate that the time-dependent Krieger-Li-Iafrate approximation in combination with the exchange-only functional violates the `Zero-Force Theorem'. By analyzing the time-dependent dipole moment of Na5 and Na9+, we furthermore show that this can lead to an unphysical self-excitation of the system depending on the system properties and the excitation strength. Analytical aspects, especially the connection between the `Zero-Force Theorem' and the `Generalized-Translation Invariance' of the potential, are discussed.

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Michael Mundt, Stephan Kümmel, Robert van Leeuwen, Paul-Gerhard Reinhard. 2007-05-09. Violation of the `Zero-Force Theorem' in the time-dependent Krieger-Li-Iafrate approximation. https://doi.org/10.1103/physreva.75.050501

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